test: improve ng build flags for cli-hello-world (#22808)

Remove unnecessary --build-optimizer flag and add --sourcemaps flag to
generate source maps for better debugging.

PR Close #22808

integration/cli-hello-world/package.json

@@ -5,7 +5,7 @@
   "scripts": {
     "ng": "ng",
     "start": "ng serve",
-    "build": "ng build --prod --build-optimizer",
+    "build": "ng build --prod --sourcemaps",
     "test": "ng test --single-run",
     "lint": "ng lint",
     "e2e": "ng e2e",